Marking member containing magnetized material



Patented Feb. 5, 19.52

MARKING MEMBER-CONTAINING MAGNETIZED MATERIAL Charles S. Allyn, Jr., Dayton, Ohio, assignor to The National Cash Register Company, Dayton, Ohio, a corporation of Maryland No Drawing. Application July 22, 1949, Serial No. 106,316

1 Claim. (Cl. 106-19) This invention relates to a marking member containing permanently magnetized material, and more particularly pertains to one having a base of erodable material, such as wax, in which is incorporated permanently magnetizable material in fine particle form which is magnetized thereafter.

Such a marking is useful in recording data on record material by making marks thereon, the erosion of the base material carrying with it a proportional amount of the magnetized material. The transferred magnetized material may be sensed by ordinary magnetic pickup devices.

In applicant's copending application for United States Letters Patent, Serial No. 106,315, now abandoned, filed on the same day as this appli cation, there is disclosed a marking member having an erodable base substance in which is incorporated, in fine particle form, unmagnetized permanently magnetizable material, and when that marking member is applied to record material, the eroded base substance carries with it a proportional part of the unmagnetized magnetizable particles, so that the record material may thereafter be placed in a magnetic field to activate the marks magnetically.

Therefore, it is an object of this invention to provide a marking member having included and dispersed therein fine particles of permanently magnetized magnetizable material.

With this and other objects in view, the invention includes certain novel features, the essential elements of which are set forth in appended claim and a preferred form or embodiment of which is hereinafter described.

The marking member of this invention not only may contain magnetizable material which is of itself a visible pigment rendering the mark which it makes visible, but may also contain additional coloring agents if desired to give a deeper or different color to the mark.

Among the magnetic substances which may be used are magnetic F9304, which is of itself a black pigment; hard steel powder; and aluminumnickel-cobalt-iron magnetic alloys. These magnetizable substances are used in fine particle form. The smaller the particle size, the better they are dispersed in the base material and the more even their deposition on the record material when a mark is made thereon with the marking member. A powdered form of these materials need not be less in particle size than that which will pass a 325-mesh screen. I

For the base material, the ordinary waxes used in wax crayons are best, although gelatin and erodable synthetic resins may be used in their place. Among the waxes may be mentioned carnauba wax, beeswax, paraffin, and the like, plasticized as desired to give the necessary erodability.

Following are typical base materials in parts by weight:

It has been found that or per cent, by volume, of magnetic material may be incorporated in the base material without materially interfering with the writing quality of the marking member-that is to say, the ease with which it may be moved over the record materialor without materially interfering with the integrity of the structure of the marking member from a strength standpoint. After the powder is incorporated in the base material the resulting member is placed in a magnetic field to magnetize the particles. With 50 to 60 per cent, by volume, of the marking member being magnetizable material, enough can be transferred by a mark made on record material, as in ordinary handwriting, to enable it to induce voltage in a standard magnetic pick-up device.

Suitable dyes may be added to the base material to enhance the color over that of the natural color of the other ingredients, if desired.

The invention is not to be deemed limited to the particular base materials or magnetic materials named, as it is obvious that selection of other materials is well within the skill of those familiar with erodable marking members and with magnetic materials.

In making such marking members, the base materials may be softened and the powdered magnetic material incorporated therein by stirring, mixing, or kneading, or the base material may be finely comminuted and intimately mixed with the magnetic powder. The waxes may be softened by heat, or melted, and the powdered magnetic material mixed therein, the marking member being shaped by any means such as molding or casting. If desired, the base material may be dissolved in an evaporable solvent 3 and the magnetic powder incorporated in the solution by stirring.

What is claimed is:

A marking member comprising an erodable base material having dispersed therein a sumcient quantity of fine particles of permanently magnetized material so that with each mark made with the member, a sensible amount of magnetized material is transferred therewith, said magnetized material resulting from magnetizing 10 magnetizable material while dispersed in thebase: material.

CHARLES JR! REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

